The present invention generally relates to a printer for use in data processing, and more particularly, to a control arrangement for a printer for printing bit images according to data input from a data processor such as a host computer.
Generally, data fed from a data processor such as a host computer, etc. includes printing data representing an actual printing pattern and control data for controlling printing method and mode of a print engine of the printer. A control apparatus (referred to merely as a controller hereinafter) for the printer processes the data for transformation thereof into dot images or bit map images to be actually printed out and sends the bit map images to the print engine.
In order to improve processing capacity or through-put of a printer, it has been a conventional practice to adopt an advanced or preliminary paper feeding method which effects paper feeding for the printing of a next page during printing of a present page (referred to as preliminary paper feeding hereinafter). In this practice, however, when predetermined printing conditions are altered, it has been necessary to once suspend the printing. Otherwise, for example, when a paper feeding port is to be altered (i.e., when sizes or direction of paper sheets are to be changed), there has been such an inconvenience that the printing is undesirably made on a paper sheet of a size different from that originally intended, since the paper sheet has already been fed as referred to above. Meanwhile, in a printer which employs a sorter for controlling images to be printed for each sheet, there is a problem that the image being printed through is delayed by one page.